PHASE EQUILIBRIA IN THE Cu2Se - Cu3SbSe4 - Cu2SnSe3 SYSTEM

Copper-tin and copper-antimony chalcogenides have received increasing attention as promising thermoelectric materials due to their high efficiency and low toxicity. Many of these phases are synthetic analogues of natural copper chalcogenide minerals and have been drawing more interest for the development of new environmentally friendly materials. In this regarding, we studied phase equilibria in the Cu2Se - Cu3SbSe4 - Cu2SnSe3 system using Differential Thermal Analysis (DTA), Powder x-ray Diffraction (PXRD) and Scanning Electron Microscope (SEM). Based on experimental data, a number of polythermal sections, the solid-phase equilibria diagram at 600 K and a projection of the liquidus surface were constructed for the title system. The system has revealed limited regions of solid solutions based on ternary compounds Cu3SbSe4 (α) and Cu2SnSe3 (β). It has been established that the liquidus surface consists of three regions corresponding to primary crystallization (HT-Cu2Se), as well as α- and β-phases.